Chlorinated stilbyl naphthotriazole brighteners



E 19.70 R. ZWElDLER ETAL 3,525,741

CHLORINATED STILBYL NAPHTHOTRIAZOLE BRIGHTENERS Original FiledSept. 23,1965 2 Sheets-Sheet :2

WHITENESS -TlME DIAGRAM N- t l CH =CH U) N y g I v NoSO CL l l I I I I i+5 +6 +4 +2 0 -2 -4 6 -e "7149/7/06 A whiteness (A H -H Rein/2amZwe/d/er H Hunter Unit of which yellow hue no longer P0670 discerniblein whilel96 on Hunfer Scale) X el r H White Effect Measured 1 (HunterUnits) United States Patent Office 3,525,741 Patented Aug. 25, 19703,525,741 CHLORINATED STILBYL NAPI-ITHOTRIAZOLE BRIGHTENERS ReinhardZweidler, Basel, Rudolf Keller, Riehen, near Basel, and Max Keller,Riehen, Switzerland, assignors to Geigy Chemical Corporation,Greenburgh, N.Y., a corporation of Delaware Continuation of applicationSer. No. 489,655, Sept. 23, 1965, which is a continuation-in-part ofapplication Ser. No. 381,906, July 10, 1964. This application Nov. 21,1967, Ser. No. 684,872 Claims priority, application Switzerland, July 9,1964, 9,043/64 lint. Cl. C0711 55/02; Clld 9/44 US. Cl. 260-240 10Claims ABSTRACT OF THE DISCLOSURE Certain new chlorinated mononaphthotriazolyl stilbenes are provided which are useful as optical brightenersand are particularly characterized by their exceptional stability in thepresence of chlorine bleaches.

This application is a continuation of application; Ser. No. 489,655,filed Sept. 23, 1965, which was in turn a continuation-in-part ofapplication Ser. No. 381,906, filed July 10, 1964. Both of said earlierapplications are now abandoned.

This invention relates to new optical brighteners, and more particularlyto new blue-fluorescent chlorinated mononaphthotriazoles which aresubstantive to and produce an improved whitening eifect on textile fibermate rials, especially on cellulosic fibers such as cotton and onsynthetic polyamide fibers such as nylonl.

It is well known that white textile material such as mens shirts, ladieswhite dresses, underwear, bed-linen and the like are given a whiterappearance by adding to the washing agents used for their cleaningcertain amounts of optical brighteuers. Due to the fact that moderntextile cellulosic materials, in particular cotton materials, are givenincreasing contents of textile finishes in the form of synthetic resins,for instance as anti-crease finish in dry state, and so-called non-resinfinishes which yield so-called cross-linked cellulose as anti-creasefinish in wet state, it is necessary to apply larger amounts of theaforesaid optical brighteners to such modern textile materials, than hadbeen required in the past in order to achieve at least the same orpreferably whiter whitening effect.

Blue fluorescing unchlorinated mono-naphthothiazolyl-stilbenes have beenused as whitening agents in washing agents, detergents and washingliquors for the aforesaid textile materials free from active chlorineand also in such agents and liquors which contained a moderate amount ofactive chlorine.

However, in applying such increased amounts of brightening agents,particularly those of the mononaphthotriazolyl-stilbene series, to themodern textile materials, the latter often assume an undesirablegreenish shade, which becomes more and more pronounced, the moreparticularly of cotton and nylon fabrics in a single containing thesebrightening agents.

At the same time, laundering of textile fibers and fabrics of celluloseand/or synthetic polyamide fibers, and more particularly of cotton andnylon fabrics in a single bath permitting simultaneous cleaning,whitening and bleaching is increasingly in demand.

Moreover, washing liquors and detergents for preparing them are nowpreferred which contain higher amounts of active chlorine than in thepast, with a view of better sanitation, for example contents in therange of 0.5 to

0.6 gram per liter of active chlorine instead of the lower contents of0.1 to 0.3 gram per liter preferred in wash liquors only a few yearsago. Detergents and washing liquors prepared therefrom, that are toserve for cleaning, Whitening and bleaching at one and the same time,must therefore contain brightening agents which are stable at the highconcentrations of active chlorine now required. In modern detergents ofthis type, the brightening agents should be stable for at least severalweeks especially during long periods of storage even under adverseclimatic conditions such as high temperatures in summer and high degreesof humidity. Active chlorine is suppled in the wash liquors fromchlorine-releasing compounds contained, e.g., in the detergents, amongwhich compounds sodium dichloroisocyanurate is especially preferred.

The best commercially used mono-naphthotriazolylstilbene brightenerswhich had shown very satisfactory fluorescence and also satisfactorybuild up with intensified White effect after repeated washings, failedto yield satisfactory results in the new detergents and liquors ofhigher chlorine content.

Moreover, when not used by industrial chemists but, for example, by ahousewife, many of the previously known optical brightening agentshaving a basis of mononaphthotriazoyl-stilbene compounds have greatdisadvantages. Often the drawing power is insuflicient at the relativelylow application temperatures to C.) preferred in such non-industrialapplications. If certain commercial products having particular aflinityto the fibers are used under the lower temperature conditions described,spots due to bad levelling power occur on the treated goods. Also, theWater-solubility of products having the necessary afiinity to the fibersat higher temperatures is often too slight at low temperatures whichalso causes spots to appear on the treated materials.

It has now been found that the above-described severe and manifolddemands made on optical brighteners under modern washing conditions aremet satisfactorily and fully by novel compounds the free acid form ofwhich is of the formulas Ho 3's and l Hoa n and, with the exception of anoticeable lower fluorescence effect on nylon, also by a novel compoundthe free acid form of which is of the formula (II-A) as well as thedisulfonated analogs of Formulas II and II-A which possess a second -SOH group in 5- or 6-position at the naphthyl nucleus and particularly bythe salts of these compounds with monovalent cations, especially alkalimetal or ammonium ions.

The satisfactory whitening properties of these two CHEQA (III) shows amarked loss of fluorescence in wash liquors having higher contents (0.5to 0.6 g. per liter) of active chlorine, known compounds obtained fromthe above compound III by introduction of one or two chlorine atoms intothe benzene ring A'thereof which chlorinated compounds are designated byIV, V and VI in Table I below, show a marked decrease of fluorescence,compared with that of the chlorine-unsubstituted compound, especially onnylon fabrics laundered in wash liquors free from chlorine andcontaining the respective brightenings in amounts necessary forachieving equal degree of whiteness on cotton, as shown by fluorescencedata given in Table I below, measured on a fluorometer of Type 240manufactured by Schildknecht A. G., Zurich, Switzerland.

It is, therefore, very surprising that the 2,4-dichloroand especiallythe 3,4-dichloro-substituted compounds I and H, the data of which arealso giveni in Table I below, show fluorescence effects on nylon whichare in the same range (compound II) or even surpass (compound 1) thoseof the corresponding ring A-unsubstituted compound III and which are bymore than 25% (compound II) and even 40% (compound 1) higher than theeffect attained under the same conditions with a more thanthree-to-five-fold amount of the structurally closest re- Also inwashings on cotton with wash liquors containing about 3.50 mg. per literof brightener and about 0.6 gram per liter of active chlorine,fluorescence values achieved with compounds I and II are by 36% and 30%,respectively, higher than the fluorescence achieved under the sameconditions with the 2,6-dichloro isomer V, while the fluorescence valueof the latter is more than 18% below that of the ring A-unsubstitutedanalog HI.

Moreover, both compound I and compound H give commercial wash products,especially heavy-duty nonsoap detergents of the Tide and Syndet type, awhiter appearance more appealing to a significant proportion of thepublic similar to the whitening achieved with ring A- unsubstitutedanalog III and compound IV, monochlorinated in ortho-position, a factwhich is especially unexpected since the para-monochloro derivative VIand the 2,6-dichloro compound V impart to the same wash powderspronounced discoloration.

A most unexpected superiority of the novel compounds of Formulas I, IIand II-A and their salts and disulfonated analogs according to theinvention is, however, shown in the stability of these novel compoundsin nonsoap detergents containing chlorine-yielding agents, es-

pecially the above-mentioned sodium dichloroisocyanurate or similarsuitable substances, mentioned further below.

This is illustrated in the accompanying drawing in which Diagrams I andII show the white etfects achieved on cotton with a non-soap detergentcontaining dichloroisocyanurate and one of the chlorine-substitutedstilbene brighteners listed further below, after such detergent had beenstored for 32 and 64 days, respectively.

Tested chlorinated stilbene brighteners are those falling under theformula:

namely the known compounds in which R represents and and the novelcompounds according to the invention in which R represents:

white effects of which are given in Diagram I, and the disulfonatedcompounds falling under the formula:

and

NaOaS represents:

and

as Well as those compounds in which the second SO Na group is inS-position at the naphthalene nucleus and R represents:

and

The White effect was measured in units on the Hunter scale above thelimit value of 96 at which the average human eye begins to see purewhite free from yellowish hues, the so'called neutral white(hydrogen-peroxide bleached cotton attains a value of about 89 on theHunter scale, which corresponds to about 86% of the highesttheoretically attainable white of freshly prepared magnesium oxide takenas 100%). Nowadays, values above 96 which correspond to white with aslight bluish cast are preferred (viz. Hunter, New Reflectometer and ItsUse for White ness Measurement in J. Opt. Soc. Am., 50, page 48 (1960).

The tests for determining the white effect on cotton after the aforesaiddifferent storage times were carried out as follows:

A detergent composition was prepared by admixing grams of the respectivebrightener to be tested with 2500 grams of sodium tripolyphosphate,mixing intimately in an Osterizer sold by I. Oster Manufacturing Co.,Milwaukee, Wis., and storing at about 25 C. in air of 90% humidity untilconstant weight has been attained. The resulting tripolyphosphatecomposition has a moisture content of about 3%. This tripolyphosphatecomposition is then mixed with sodium dichloro-isocyanurate in a Weightratio of 85:15. 0.5 gram of the resulting detergent composition wasadded to 100 milliliters of cold water in a washing apparatus and acotton cloth weighing 3.3 grams was immersed in the resulting washliquor immediately after its preparation. The liquor was then heated to60 C. and the cotton cloth was washed at that temperature for 15minutes. The cloth was then washed well first in luke-warm and then incold water and subsequently air-dried. The white elfect of the treatedcloths was determined by comparison with standard samples showingdegrees of whiteness corresponding to values ranging from 89-109 on theHunter scale.

The same test was repeated with each time 0.5 gram of the aforesaiddetergent composition which has been stored for thirty-two andsixty-four days, respectively.

The results were plotted in Diagrams I and II.

Storage was effected in sealed bottles at an ambient temperature ofabout 29 C. and an atmospheric humidity of 92%.

These tests reveal that, surprisingly, the compounds according to theinvention show satisfactory pure white effects on cotton when stored inmixture with sodium dichloroisocyanurate-containing detergents evenafter 64 days, While known chlorine-substituted isomers and analogs ofthe compounds of the invention fail already after less than half thattime affording only brightening effects of noticeable yellowish hues.

This renders them unsatisfactory when used in nonsoap detergentscontaining chlorine-yielding agents since a time span of six weeks frommanufacturer to consumer must be considered a minimum.

In view of their good resistance to active chlorine, the compoundsaccording to the invention are well suited for use in wash liquorscontaining such chlorine in amounts up to about 0.6 gram per liter andhigher, up to 0.8 and even 1.5 grams per liter, although in the lattercase, it is recommended that the Wash liquors are preferably not leftstanding for more than one hour, especially at temperatures above 50 C.

Preferably, the wash liquors contain not more than 0.6 gram per liter ofactive chlorine. Of course the compounds of Formulas I and II can alsobe used with equally satisfactory effect in wash liquors which containno active chlorine.

The compounds of Formulas I and II are used in concentrations of 0.0005to 0.1% calculated on the weight of the textile goods to be whitened,and are added to the wash liquors in amounts of from 0.001 to 0.05 gram,preferably about 0.003 to 0.01 gram per liter, depending upon the numberof washing operations to be performed with one of the same liquor andthe goods-to-liquor weight ratio to be applied. The latter ranges fromabout 1:50 to 1:3 preferably 1:30 to 1:20 in the case of manuallaundering and 1:8 to 1:3 when using washing machines.

A Wash liquor as conventionally applied for the washing of cotton ornylon material contains about 2 to 5 grams per liter of wash powder,which determines the concentration of the compounds of the invention, Iand II, in the latter, and from about 0.1 to 0.6 gram of active chlorineper liter, the content of active chlorine being the higher, the shorterthe goods-to-liquor ratio.

Due to the good resistance of the brightening compounds I and II againstactive chlorine, the aforesaid wash liquor can be left standing for aprolonged period, e.g. about two hours, at temperatures of 50 C. to C.

Textile materials of cellulosic or synthetic polyamide fibers washedwith the aforesaid wash liquors possess an attractive white appearancewith a desirable faint violetbluish hue. Repeated laundering (10 to 20times and more) with wash liquors having relatively high concentrationsof the brightening compounds I or II further improve this pleasantappearance, without producing an undesirable faint residual hue e.g. ofpink or green.

Increasing whiteness after repeated washings is also referred to asbuild-up and is particularly strong in the case of the compoundsaccording to the invention, and especially compound I.

Textile materials of cellulosic fibers, especially cotton, or ofsynthetic polyamide fibers, especially nylon (nylon 6, nylon 66 etc.)are laundered with the wash liquors containing compound I and/or IIunder conventional conditions, e.g. at temperatures of 30 to 80 C. Whenlaundering has been carried out with wash liquors having a high contentof active chlorine, it is recommended that the laundered textile goodsbe rinsed with Water to which a de-chlorinating agent such as sodiumbisulfite has been added in conventional concentration.

Active chlorine can be introduced into the abovedescribed wash liquorsin any conventional manner, for instance, in the form of water-solublesalts of hypochlorous acid such as lithium, sodium or potassiumhypochlorite, and in detergents also in the form of diortri-chlorocyanuric acid or their sodium or potassium salts;N-chloro-dicarboxylic acid imides, such as N-chloro succinimide orN-chloro-malonimide, or chlorohydantoins such as1,3-dichloro-5,S-dimethylhydantoin. In detergents, the chlorine-yieldingagent is added in amounts not exceeding 20% and preferably not more than15-16% by Weight or less, calculated on the weight of the detergent.

Detergents usable in the wash liquors are ionogenic agents such assoaps, water-soluble salts of higher fatty alcohol sulfates, higheralkyl and/ or polyalkyl-substituted aryl sulfonic acids, esters ofmedium to higher alkanols and sulfocarboxylic acids; higheralkanoylamino-arylcarboxylic or -sulfonic acids, or fatty acid glycerinsulfonates; also usable are non-ionogenic detergents such as higheralkylphenol-polyglycol ethers.

Furthermore, the above-described wash liquors may also containconventional adjuvants such as alkali metal polyphosphates or-polymetaphosphates, alkali metal silicates, alkali metal borates,especially perborates, alkali metal salts of carboxy-methyl cellulose,foam stabilizers, such as alkanol amides of higher fatty acids, orcomplexformers such as water-soluble salts of ethylene diaminotetracetic acid.

The alkali metal salts of the compounds of Formulas I and II areobtained by coupling the diazo compound of4-amino-3',4'-dichloro-stilbene-2-sulfonic acid or 4-amino-2,4'-dichloro-stilbene-2-sulfonic acid with a 2- aminonaphthaleneoptionally sulfonated in position l, and by oxidizing by conventionalmethods the o-aminoazo dyestutf obtained in the form of the alkali metalsalt, in .particular the sodium or potassium salt, to form thenaphthotriazole compound.

The 4-amino-3',4-dichloro-stilbene-Z-sulfonic acid or4-amino-2,4-dichloro-stilbene-Z-sulfonic acid, respectively, which areused as starting materials are obtained, by known methods, for instanceby the condensation of 3,4-dichlorobenzaldehyde or2,4-dichloro-benzaldehyde with 4-nitro-toluene-2-sulfonic acid phenylester, saponification of the sulfonic acid phenyl ester group andreduction of the resulting 4-nitro-3',4'-dichloro-stilbene- 2-sulfonicacid or 4-nitro-2',4'-dichloro-stilbene-2-sulfonic acid.

The coupling of the diazotized 4-amino-3',4'-dichlorostilbene-Z-sulfonicacid or 4-amino-2',4-dichloro-stilbene- 2-sulfonic acid with theabove-mentioned Z-aminonaphthalene is effected by conventional methodsand preferably in aqueous pyridine solution; oxidation of the o-aminoazodyestulf to form the naphthotriazole compound of Formulas I or II isperformed, e.g. with oxygen or air in the presence of copper (II) salts,in particular ammonia complexes of copper sulfate, which act ascatalysts.

In all of the following examples the sodium salts of the2-(3"',4"-dichloro-stilbyl-4")-(naphtho 1',2:4,5) 1,2,3-triazole-2"-sulfonic acid or 2-(2,4"-dichloro-stilbyl- 4" (naphtho- 1',2' 4,5 l ,2,3-triazole-2"-sulfonic acid are obtained. These compoundscan be converted easily by conventional methods to low-soluble compoundssuch as alkaline earth salts, e.g. magnesium or calcium salts. However,and this goes for the whole 2-(stilbyl-4")-(naphtho-1,2:4,5)-1,2,3-triazole-2"-sulfonic acid salt group ofcompounds, the free sulfonic acid cannot be obtained by acidifying asolution, e.g. of the sodium salt, of such a compound. In order toproduce free sulfonic acids of this group of compounds, a novel methodhas to be used. Thus, for instance, the sodium salt has to be convertedwith phosphorus oxychloride to the corresponding sulfonic acid chloridewhereupon the sulfonic acid chloride has to be saponified with aqueousalkanol (via the unstable sulfonic acid alkyl ester) to form the freesulfonic acid.

The resulting free sulfonic acids can be neutralized with alkalihydroxides such as potassium hydroxide, lithium hydroxide, furthermorewith ammonium hydroxide and various aliphatic and heterocyclic aminessuch as diethyl amine, triethyl amine, monoethanol amine, diethanolamine, triethanol amine, morpholine, pyridine, pyrrolidine,pi-peridine,, etc., to form the corresponding salts of the unsubstitutedand substituted derivatives of 2- stilbyl-4" (naphtho- 1 ',2 :4,5)-1,2,3-triazole-2"-sulfonic acid, more particularly, the correspondingsalts of the compounds of Formulas I and II.

The following non-limitative exmaples illustrate the invention. Wherenot otherwise stated, parts and percentages are given therein by weight.The temperatures are in degrees centigrade. The relationship of parts byweight to parts by volume is that of grams (g.) to milliliters (ml.).

EXAMPLE l 5 1 Na S 0 34.4 g. of 4-amino-3',4'-dichlorostilbene 2sulfonic acid together with NaOH are dissolved in 800 g. of water sothat the solution becomes neutral. 7.0 g. of sodium nitrite are added tothis solution. While stirring well, the mixture is added dropwise at a810 to a solution of 12.8 g. of hydrochloric acid in 100 g. of Water.Then the whole is stirred for another 30 minutes at 810, the

excess nitrite is removed by means of a small amount of sulfamic acid,and the diazo suspension thus obtained is poured at a temperature of 5to +2 into a solution of 14.2 g. of .2-aminonaphthalene in 900 g. oftechnical pyridine. On completion of the coupling, NaOH is added to themixture until phenolphthalein shows an alkaline reaction. Upon additionof 180 g. 0g sodium chloride, the mixture separates into two layers. Theupper, pyridine layer containing the o-aminoazo dyestuff is then mixedwith a solution of 2.5 g. of crystallized copper sulfate in g. of waterand 10 g. of monoethanol amine (hereinafter referred to as coppercatalyst). Now a vigorous stream of air is conducted at a temperature of9597 into the quickly stirred reaction mixture until the red o-aminoazodyestuflf has been completely oxidized to the naphthotriazole compound.Then the copper salts are precipitated by the addition of a small excessof sodium sulfide and the copper sulfide is separated from the boilinghot solution by filtration. The aqueous pyridinic solution of triazoleis now heated to boiling by direct introduction of steam and is mixedwith 5 g. of sodium hydrosulfite whereupon the pyridine is evaporated bysteam distillation. As soon as the major part of the crude triazolecompound is removed, the steam distillation is discontinued, the mixtureis slightly cooled and the crystal cake filtered 01f by suction andthoroughly washed with warm water. For further purification, the crudeproduct is dissolved under slight reflux in about 70% aqueous technicalpyridine to which some NaOH is added. Then it is cooled, and theseparated product is filtered 01f, slurried with some NaOH and Water andagain subjected to steam distillation to remove the excess pyridine.After complete removal of the pyridine, the mixture is slightly cooled.The precipitate is filtered off while still warm and washed on thefilter with warm water. The product obtained in this Way is stirred forabout 30 minutes at reflux temperature in 96% alcohol and is thencooled, filtered ofl? by suction, washed thoroughly on the filter withalcohol and then dried in vacuo at a temperature of 125.

The purified naphthotriazole compound must be examined as to whether itcontains coloring impurities. 200 mg. of the product dissolved in 10 g.of dimethyl formamide should give a solution which is colorless inultraviolet-free daylight. If the solution shows a yellowish coloring,the above-described purification steps should be repeated.

The sodium salt of the 2-(3,4'"-dichlorostilbyl-4")-(naphtho-1,2':4,5)-1,2,3-triazole-2"-sulfonic acid is obtained as a paleyellowish-green powder melting at a tem perature higher than 300.

This compound is a valuable brightening agent for cellulose fiber,polyarnide fibers, soap powders, detergents, etc. It has good fastnessnot only to washing and light, but also excellent fastness properties tochlorine and chlorites on substrates, in the dye liquors and inpulverulent mixtures.

The 4-amino-3,4'-dichlorostilbene-Z-sulfonic acid used as startingmaterial is prepared in the following manner At an initial temperatureof about and later g. of 3,4-dichlorobenzaldehyde are added in smallportions during 8 hours to a solution of 293 g. of 4-nitro-toluene-Z-sulfonic acid phenyl ester in 150 ml. of dry toluene towhich 7 g. of piperidine have been added. The mixture is kept under mildreflux. The separating Water is continuously removed by a waterseparator. After a reaction period of about 22 to 24 hours, the crudereaction product is slightly cooled and introduced into a mixture of 280g. of methanol and 82.5 g. of potassium hydroxide within 1 to 2 hours ata temperature of 30-35. Then the reaction mixture is heated within 1hour to a temperature of 62 to 64 and stirred for another 3 hours undermild reflux. The mixture is cooled to 25, stirred for 1 hour andfiltered, and the residue is washed first with 50 g. of methanol andthen with a solution of 5 g. of

sodium chloride in 100 g. of water. The crude product thus obtained ispurified by recrystallization from boiling water and precipitated againcompletely by the addition of sodium chloride. The damp sodium salt of4-nitro-3',4- dichlorostilbene 2-sulfonic acid is then reduced to the 4-amino-3',4-dichlorostilbene-Z-sulfonic acid according to the Bchampprocess by means of iron and hydrochloric acid. The free sulfonic acidis obtained as a pale beige powder melting at a temperature higher than300.

By repeating Example 1, but using in lieu of 2aminonaphthalene anequivalent amount of Z-aminonaphthalene- -sulfonic acid or2-amino-naphthalene=6-sulfonic acid, there are obtained sodium2-(3"',4'"-dichloro-stilbyl-4") (naphtho-1',2' :4,5)-1,2,3-triazole-2",5'-disulfonic acid and 2,6-disulfonic acid,respectively.

EXAMPLE 2 l/ NaSO N A solution of the sodium salt of 34.4 g. of 4-amino-3',4-clichloro stilbene-2-sulfonic acid and 7.0 g. of sodium nitrite in800 ml. of water is indirectly diazotized at a temperature of 810 bypouring it into a solution of 12.8 g. of hydrochloric acid in 100 ml. ofwater. The diazo suspension is then added within 3 hours at atemperature of 5 to to a solution of 22.7 g. of2-aminonaphthalene-l-sulfonic acid in a mixture of 900 g. of technicalpyridine and 50 ml. of water. Upon completion of the diazo-reaction,stirring is continued for a short time, the 14.4 g. of sodium hydroxidein the form of a 30% aqueous solution is added until phenolplithaleinclearly shows an alkaline reaction, whereupon 200 g. of sodium chlorideare added. The mixture is left standing for a short time. Two layers areformed which are separated and, after addition of the copper catalystdescribed in Example 1, the pyridinic dyestuif solution is oxidized withair to the naphtho-triazole compound. Removal of the copper salts andpurification of the crude product is effected in the same manner asdescribed in Example 1. The sodium salt of the2-(3"',4"-dichloro-stilbyl-4)-(naphtho-l:4,5)-l,2,3-triazole-2"-sulfonic acid is obtained as a paleyellowish-green powder having a melting point above 300. The product isidentical with the compound described in Example 1.

By repeating Example 2, but using in lieu of 34.4 g. of sodium4-amino3,4-dichloro-stilbene-Z-sulfonate an equivalent amount of sodium4-amino-3-chloro-stilbene- 2-sultonate, there is obtained thecorresponding compound of Formula 1.

EXAMPLE 3 NaSO;

A solution of 34.4 g. of 4-amino-2',4-dichlor0-stilbene- 2-sulfonicacid, 4.1 g. of sodium hydroxide and 6.9 of sodium nitrite in 800 ml. ofwater is indirectly diazotized by adding it dropwise at a temperature of8-10" to a solution of 12.8 g. of hydrochloric acid in 100 ml. of water.The suspension of the diazo compound obtained in this manner is thenadded within 30 minutes at a temperature of -5 to +2 to a solution of14.5 g. of 2-amino naphthalene in 900 g. of technical pyridine. Oncompletion of coupling, about 30% aqueous sodium hydroxide solution isadded until phenolphthalein shows an alkaline reaction. 180 g. of sodiumchloride are added,

stirred for a short time and left standing whereupon the upper pyridinelayer containing the o-aminoazo dyestutf is separated. Now, a coppercatalyst consisting of 2.5 g. of crystallized copper sulfate and 10 g.of monoethanolamine in ml. of water is added, and the reaction mixtureis heated to a temperature of 95-97. At the same time a vigorous streamof air is introduced with rapid stirring until the red color hasdisappeared, and the oarninoazo dyestufi has been converted to thetriazole compound. Subsequently, the copper salts are converted tocopper sulfide by the addition of a small excess of sodium sulfide andfiltered off. After the addition of 5 g. of sodium hydrosulfite, thepyridine is removed with the aid of steam until the major portion of thecrude prod not has been precipitated. The cooled solution is filteredoff, the filtrate is washed well with warm water, the crude product isrecrystallized as described in Example 1 from 70% aqueous technicalpyridine, the adhering pyridine is removed and other colored by-productsare extracted with alcohol. The purified sodium salt of2-(2",4"-dichloro-stilbyl-4)-(naphtho-1',2:4,5 )-1,2,3 triazole 2"-sulfonic acid is obtained as a pale yellowish powder having a meltingpoint above 300. The compound is a valuable brightening agent forcellulose fibres, soap powders, detergents and the like and, whendissolved in a wash liquor or used on a substrate, has excellentfastness to active chlorine and chlorites.

Preparation of 4-amino-2',4'-dichloro-stilbene-Z- sulfonic acid At aninitial temperature of about which is then raised to g. of2,4-dichlorobenzaldehyde are added in small portions Within 8 hoursunder mild reflux to a solution of 293 g. of p-nitrotoluene sulfonicacid phenyl ester in 150 g. of dry toluene to which 7 g. of piperidineare added. The separating water is continuously removed by means of aseparator. After a total reaction period of about 22m 24 hours, thecrude reaction product is cooled and introduced within 1 to 2 hours at atemperature of 30 to 35 into a mixture of 280 g. of methanol and 82.5 g.of otassium hydroxide solution. Then the reaction mixture is heated for1 hour to a temperature of 62 to 64 and stirred for another 3 hoursunder mild reflux. It is cooled to 25, stirred for 1 hour, and filtered.The residue is washed first with water, then with a solution of 5 g. ofsodium chloride in 100 ml. of water. The crude product thus obtained iscleaned by recrystallization from boiling water and again completelyprecipitated by the addition of sodium chloride. The wet sodium salt of4-nitro-2',4'-dichloro-stilbene-2-sulfonic acid is then reducedaccording to the Bchamp method by means of iron and hydrochloric acid toform 4-amino- 2',4'-dichloro-stilbene 2 sulfonic acid. The free sulfonicacid is obtained as a pale beige powder having a melting point above300.

By repeating Example 3, but using in lieu of 14.5 g. ofZ-amino-naphthalene an equivalent amount of 2-amino-naphthalene-5-sulfonic acid, there is obtained the corresponding2,4"'-dichloro stilbyl substituted naphthotriazole-2",5'-disulfonicacid.

EXAMPLE 4 C1 C.@CH:CH@ N N A solution of the sodium salt of 34.4 g. of4-amino- 2',4-dichloro-stilbene-Z-sulfonic acid and 6.9 g. of sodiumnitrite in 500 ml. of water is indirectly diazotized at a temperature of8 to 10 by pouring it into a solution of 12.8 g. of hydrochloric acid in100 ml. of water. Then, at a temperature of 5 to 10, this suspension ofthe diazo compound is added within 3 to 4 hours to a solution of 22.7 g.of 2 aminonaphthalene-l-sulfonic acid in a mixture of 600 g. oftechnical pyridine and 100 ml. of water. On completion of thediazo-reaction, stirring is continued for a short time, then 14.5 g. ofsodium hydroxide in the form of a 30% aqueous solution is added untilphenolphthalein shows a clearly alkaline reaction, whereupon 140 g. ofsodium chloride are added. The mixture is left standing for a shorttime, two layers form which are separated anid, after addition of thecopper catalyst described in Example 1, the pyridinic dyestuff solutionis oxidized with air to form the triazole compound. After working up andpurifying as described in Example 1, the sodium salt of 2-(2"',4"'-dichloro-stilbyl-4")-(naphtho l',2':4,5)-1,2,3 triazole- 2"-sulfonicacid is obtained as a pale yellowish powder having a melting point above300". The product is identical with the compound described in Example 3.

EXAMPLE 5 0.09 g. of active chlorine in the form of an aqueous sodiumhypochlorite solution is added to a wash liquor at a temperature of 60containing 1.5 g. of a detergent which consists of 8 parts of laurylsulfate, 11 parts of dodecyl benzene sulfonate, 11 parts of sodiumtripolyphosphate, 17 parts of sodium pyrophosphate, 4.5 parts of sodiumsilicate, 1.8 parts of carboxymethyl cellulose, 37 parts of sodiumsulfate, 8 parts of sodium perborate and 1.7 parts of water as well as0.0017 g. of a brightening agent of the formula:

in 300 ml. of water. The wash liquor is left standing for 1 hour at 60and is then used for washing g. of untreated cotton fabric duringminutes at the same temperature. Then the fabric is rinsed first inlukewarm and then in cold water and is dried. The cotton fabric treatedin this manner appears highly brightened in daylight When thefluorescence of this fabric is measured on a Fluorometer, Type 240(manufactured by E. Schildknecht, Zurich, Switzerland), a fluorescencevalue of 81 is obtained.

However, when the brightening agent used in the above example isreplaced by 0.0021 g. of a compound of the formula:

and this example is otherwise repeated, an untreated cotton fabricwashed with the resulting liquor has practically the same appearance inday light as cotton fabric which has not been brightened. Measurement onthe same fluorometer gives a fluorescence value of not more than 5.

When the same washing test is performed without the addition of activechlorine, the. same visual brightening effect is obtained with thefirst-mentioned compound its fluorescence value being 108 while fabrictreated with the second-mentioned compound even shows a fluorescencevalue of 113. This shows that when the wash liquor is left standing fora long time, only the first-mentioned compound has sufiicient stabilityto active chlorine, whereas, under the same conditions, the secondcompound is practically destroyed.

Furthermore, when polyamide fabrics present irfi household laundry, suchas nylon 6, nylon 66, and the like are washed with wash liquorscontaining the first-men- 12 tioned compound, they are brightenedtogether with the cotton fabric.

EXAMPLE 6 0.09 g. of active chlorine in the form of an aqueous sodiumhypochlorite solution is added to a wash liquor at a temperature of 60containing 1.5 g. of a detergent which consists of 8 parts of laurylsulfate, 11 parts of dodecyl benzene sulfonate, 11 parts of sodiumtripolyphosphate, 17 parts of sodium pyrophosphate, 4.5 parts of sodiumsilicate, 1.8 parts of carboxymethyl cellulose, 37 parts of sodiumsulfate, 8 parts of sodium perborate and 1.7 parts of water as well as0.0020 g. of a brightening agent of the formula:

NaSO N in 300 ml. of water. The wash liquor is left standing for 1 hourat 60 and is then used for washing during 15 minutes at the sametemperature 10 g. of untreated cotton fabric. Then the fabric is rinsedfirst with lukewarm and then with cold water and is dried. In daylight,the fabric treated in this manner appears as highly brightened.Measurement of the fluorescence of this fabric on the Fluorometermentioned in the preceding example, yields a fluorescence value of 97.

When the brightening agent mentioned in the above example is replaced by0.0021 g. of a compound of the formula:

NaSO

while repeating the example in all other details, the resulting washedcotton fabric appears as untreated in daylight, i.e. it is practicallynot brightened. When measured on the same fluorometer, its fluorescencevalue is not more than 5. When the same washing test is performedwithout the addition of active chlorine in the form of an aqueous sodiumhypochlorite solution, the same visual brightening effect is obtainedwith the first-mentioned compound, its fluorescence value being 106,while the second compound gives a fluorescence value of 113.

Furthermore, if polyamide fabrics which occur in household laundry, suchas nylon 6, nylon 66 and the like, are washed with wash liquorscontaining the firstmentioned compound, they are brightenedsimultaneously with the cotton fabric.

EXAMPLE 7 Cl CH=CH The fabric is gently stirred for 15 minutes, then itis rinsed first with lukewarm and then with cold water and finallydried. The cotton fabric washed in this manner has a beautifulbrightening effect in day light. This fabric measured on the Fluorometermentioned in the preceding examples yields a fluorescence value of 101.

When this cotton fabric is treated, analogous to household practice,under the same conditions with further wash liquors of the samecomposition; the brightening effect increases gradually as shown in thefollowing table.

Without addition of chlorine- Fluorescence values Number of washings:

However, when the above-described washing process is carried out in sucha way that at a temperature of 60 and 5 minutes before introducing thecotton fabric into the wash liquor, 0.18 g. of active chlorine in theform of a sodium hypochlorite solution is addedwhile the conditions areotherwise the same as described in the above example and when the fabricis treated after washing in a dechlorination bath containing 0.3 g. ofsodium bisulfite in 300 ml. of water and lasting for 5 minutes (roomtemperature) which is applied between the lukewarm and the cold rinsingstep, the cotton fabric treated in this manner shows a fluorescencevalue of 101.

When treatment of the cotton fabric is continued under the sameconditions with further chlorine-containing wash liquors of the samecomposition, the brightening effect increases gradually as shown in thefollowing table:

With the addition of 0.18 g. of active chlorine in the form of sodiumhypochlorite- Number of washings: Fluorescence values 1 101 The samemethods and conditions are applied as in the above examples but only0.0009 g. of the brightening agent are used instead of 0.0011 g.,whereupon the following fluorescence values are obtained:

With the addition of 0.18 g. of active chlorine in the form of sodiumhypochlorite- Number of washings: Fluorescence values In this way, abrilliant white effect is obtained in spite of the active chlorinepresent in the wash liquors.

The amount of brightening agent mentioned in the above example may belargely varied. Wash liquors can be used which contain from 0.0003 g. to0.003 g. of brightening agent. The number of baths required to achievethe maximum effect changes accordingly. Further, the composition of theabove detergents can be changed. Also the amount of active chlorineadded to the liquors can be varied. Besides sodium hypochloritesolution, corresponding amounts of hypochlorite compounds can be usedwhich have been stabilized or converted to solid form, respectively.Moreover, the hypo chlorite can be replaced by other compounds supplyingactive chlorine, such as dichloroor trichloro-cyanurates, their alkalisalts or N-chloro-succinimide, N-chloromalonimide or hydantoins, such as1,3-dichloro-5,5-dimethyl hydantoirl.

The measured fluorescence values vary with the time period before theintroduction of the cotton fabric and with the temperature of the washliquor.

Polyamide fabrics which may be simultaneously present in the wash, suchas nylon 6 or nylon 66, are also brightened by the above-describedwashing processes.

14 EXAMPLE 8 10 g. of an untreated cotton fabric are introduced into 300ml. of a wash liquor of a temperature of 60 containing 1.5 g. of adetergent which consists of 15.2 parts of dodecyl benzene sulfonate, 3.8parts of lauryl sulfate, 25.6 parts of sodium tripolyphosphate, 7.6parts of tetrasodium pyrophosphate, 4.8 parts of sodium silicate, 1.9parts of magnesium silicate, 5.0 parts of sodium carbonate, 1.4 parts ofcarboxymethyl cellulose, 0.3 parts of sodium ethylene diaminetetraacetate and 34.4 part of sodium sulfate, as well as 0.0011 g. ofthe compound of the formula:

Number of washings: Fluorescence values When the above-described washingprocess is carried out in such a way that 0.18 g. of active chlorine inthe form of a sodium hypochlorite solution is added at a temperature of60 and 5 minutes before introducing the cotton fabric into the washliquor, while the other conditions are the same as given in the aboveexample, and when a dechlorinaiton bath containing 0.3 g. of sodiumbisulfate in 300 ml. of water and lasting for 5 minutes (roomtemperature) is applied to the washed fabric between the lukewarm andthe cold rinsing step, the cotton fabric thus treated shows afluorescence value of 105.

When the cotton fabric is treated under the same conditions with furtherchlorine-containing w ash liquors of the same composition, thebrightening effect increases gradually as shown in the following table:

With the addition of 0.18 g. of active chlorine in the form of sodiumhypochlorite-- Number of washings: Fluorescence values Number ofwashings: Fluorescence values In this way, a beautiful white effect isobtained in spite of the amount of 0.6 g. of active chlorine present inevery liter of the wash liquors.

The amount of the brightening agent mentioned in the above example canbe largely varied. Wash liquors can be used which contain from 0.0003 to0.003 g. of brightening agent. The number of baths required to achievethe maximum efiect changes accordingly. Furthermore, the composition ofthe above-mentioned detergent can be changed. Equally, the amount ofactive chlorine added to the liquors can be varied. Moreover, thefluorescence values measured will be influenced by changes in the timeperiod between the addition of the active chlorine and the introductionof the cotton fabric as well as by changes in the temperature of thewash liquor.

EXAMPLE 9 10 g. of an untreated cotton fabric are introduced into 300ml. of a wash liquor at a temperature of 60 containing 1.5 g. of thedetergent described in Example 4 and 0.0011 g. of the compound of theformula:

The cotton fabric is gently stirred for 15 minutes. Then it is rinsedfirst with lukewarm and then with cold water and finally dried. Whenthis fabric is measured on the Fluorometer used in the precedingexamples, a fluorescence value of 106 is obtained. When this cottonfabric is treated under the same conditions with further wash liquors ofthe same composition, the brightening effect of the fabric increases asshown in the following table:

Without the addition of chlorine- Number of washings: Fluorescencevalues 1 106 5 118 122 When the above-described washing process iscarried out in such a manner that 0.18 g. of active chlorine in the formof sodium hypochlorite solution is added at a temperature of 60 and 5minutes before introducing the cotton fabric into the wash liquor, whilethe other conditions are the same as in the above example, and when adechlorination bath containing 0.3 g. of sodium bisulfate in 300 ml. ofwater and lasting for 5 minutes (room temperature) is applied to thewashed fabric between the lukewarm and the cold rinsing step, the cottonfabric treated in this way shows a fluorescence value of 95. When thiscotton fabric is treated with further wash liquors of the samecomposition, the brightening effect increases as shown in the followingtable:

With the addition of 0.18 g. of active chlorine in the form of sodiumhypochlorite- NaSOa Number of washings: Fluorescence values 1 95 5 t 10710 110 Number of washings: Fluorescence values 16 When the brighteningagent mentioned in the above example is replaced by 0.0011 g. of thecompound of the formula: I

NaSO;

the other conditions being the same as before, the following values areobtained for several washing treatments:

With the addition of 0.18 g. of active chlorine in the form of sodiumhypochlorite- Number of washings: Fluorescence values Number ofwashings: Fluorescence values When the brightening agent is replaced by0.0011 g. of the compound of the formula:

NaSOa all other conditions being the same as above, the following valuesare obtained:

With the addition of 0.18 g. of active chlorine in the form of sodiumhypochlorite- Number of washings: Fluorescence values When the sameprocess and conditions are applied as in the above example but only0.0009 g. of the same brightening agent is used instead of 0.0011 g.,the following fluorescence values are obtained:

With the addition of 0.18 g. of active chlorine in the form of sodiumhypochlorite Number of washings: Fluorescence values If the brighteningagent is replaced by 0.0011 g. of the compound of the formula:

NaSO

all other conditions being the same as above, the following values areobtained:

17 With the addition of 0.18 g. of active chlorine in the form of sodiumhypochlorite- Number of washings: Fluorescence values Number ofwashings: Fluorescence values 10 g. of an untreated nylon fabric areintroduced into 200 ml. of a wash liquor at a temperature of 40containing 1.0 g. of a detergent which consists of 15.2 parts of dodecylbenzene sulfonate, 3.8 parts of lauryl sulfate, 25.6 parts of sodiumtripolyphosphate, 7.6 parts of tetrasodium phosphate, 4.8 parts ofsodium silicate, 1.9 parts of magnesium silicate, 5.0 parts of sodiumcarbonate, 1.4 parts of carboxymethyl cellulose, 0.3 part of sodiumethylene diamine tetraacetate and 34.4 parts of sodium sulfate as wellas 0.0006 g. of the compound of the fol lowing formula:

NaSO

The nylon fabric is gently stirred for minutes, then it is rinsed firstwith lukewarm and then with cold water and finally dried. The nylonfabric washed in this manner has a beautiful white effect in daylight.When this fabric is measured on the Fluorometer used in the precedingexamples, a fluorescence value of 57 is obtained.

When this nylon fabric is treated, analogous to household practice,under the same conditions with further wash liquors of the samecomposition, the brightening effect is increased as shown in thefollowing table:

Number of washings: Fluorescence values When the brightening agentmentioned in the above example is replaced by 0.0007 g. of the compoundof the formula:

NaSOa the other conditions being the same as before, the followingfluoroscence values are obtained for several washing treatments:

Number of washings: Fluorescence values EXAMPLE 11 A heavy dutydetergent mixture consisting of Parts by wt.

Lauryl sulfate 8.2 Dodecyl-benzene sulfonate 11.0 Sodiumtripolyphosphate, (Na P O 11.0 Tetrasodium pyrophosphate 17.6 Anhydroussodium silicate 4.6 Carboxymethyl cellulose 1.4

Sodium sulfate 38.2 Sodium perborate (NaBO +4H O) 8.0 Sodium 2(2',4"-dichloro-stilbyl-4")-(naphthol',2' 4,5-1,2,3-triazole-2"-sulfonate 0.08

is produced in the following manner:

The optical brightener is intimately mixed with normal aqueous sodiumhydroxide solution (10 ml. per g. of brightener) and when the brighteneris thoroughly dispersed, about 200 to 300 ml. of water (per gram ofbrightener) are added.

The other ingredients of the detergent mixture are mixed with each otherseparately and intimately using a sufficient amount of water to obtain acreamy paste, the latter is dried at 60 and granulated.

The detergent granules are then added to the slurry of brightener andthe mixture is repeatedly and thoroughly stirred until a smooth, creamymix is obtained. The resulting slurry is then spread into a uniformlayer on a fiat surface and dried in an oven at for 16 hours. Theresulting cake is allowed to cool to room temperature, left standing forat least 30 minutes and then crushed in a desiccator. The dried chunksof detergent mixture are then forced through a 20 mesh screen and, ifdesired, the resulting powder is transferred to a 60 mesh screen toremove the fine portion.

A similar mixture is obtained by replacing the brightener in the aboveexample by 0.06 part of sodium 2-(3"', 4"'-dichloro-stilbyl 4")(naphtho-1',2':4,5)-1,2,3-triazole-2-sulfonate.

EXAMPLE 12 In a similar manner as described in Example 11 there isproduced a synthetic, non-soap, heavy-duty detergent of the followingcomposition (in percent by weight):

Dodecyl benzene sulfonate 15.2 Lauryl sulfate 3.8 Sodiumtripolyphosphate 25.6 Tetrasodium pyrophosphate 7.6 Anhydrous sodiumsilicate 4.8 Magnesium silicate 1.9 Sodium carbonate 5.0 Carboxymethylcellulose 1.4 Sodium ethylenediamine tetraacetate 0.4 Sodium 2(3"',4-dichloro-stilbyl 4")-naphtho- 1,2':4,5)-l,2,3triazole-2"-sulfonate 0.057

EXAMPLE 13 A heavy-duty non-soap detergent mixture consisting of 8 partsof lauryl sulfate, 11 parts of dodecylbenzene sulfonate, 11 parts ofsodium tripolyphosphate, 17 parts of tetrasodium pyrophosphate, 4.4parts of sodium silicate, 1.8 parts of carboxymethyl cellulose, 8 partsof sodium perborate, 37 parts of sodium sulfate and 1.7 parts of wateris worked up into a paste with a solution of 0.06 part of the sodiumsalt of 2-(3"',4'"-dichloro-stilbyl-4")- (naphtho l,2':4,5)1,2,3-triazole-2"-sulfonate in parts of water. This paste is dried at 60and then milled. In daylight, the washing powder obtained has a con- 19siderably whiter appearance than the same washing composition producedwithout the addition of the optical brightening agent.

Beautiful white Washing powders are also obtained if, instead of thebrightening agent mentioned above, 0.08 part of the sodium salt of2-(2",4"-dichloro-stilbyl-4")- (naphtho-1,2:4,5) 1,2,3triazole-2"-sulfonate is incorporated into the above washing agentpreparation.

EXAMPLE 14 A heat-liquifiable soap for use in washing machines isproduced as follows:

To a hot mixture of- 40 parts by weight of coconut oil fatty acid sodiumsoap 31 parts by weight of sodium tripolyphosphate 9 parts by Weight oftetrasodium pyrophosphate 6 parts by weight of sodium silicate 3 partsby Weight of magnesium silicate 0.5 part by weight of sodiumethylenediamine tetraacetate 5 parts by weight of sodium carbonate 5.5parts by weight of sodium sulfate and 70 parts of water,

tion is prepared, all amounts being expressed as parts by weight:

Sodium alkyl benzene sulfonate (the alkyl group being derived frompolypropylene and averaging 12 carbon atoms per molecule) 18.0 Sodiumtripolyphosphate 48.0 Water soluble sodium silicate solids 6.0 Sodiumsulfate 16.8 Monoethanolamide of coconut oil fatty acids having from to14 carbon atoms 2.7 Water, carboxymethylcellulose, tarnish inhibitor andperfume 8.5 Sodium salt of 2 (3"',4"' dichloro stilbyl 4")- (naphtho1',2,:4,5) 1,2,3 triazole 2" sulfonate 0.08

The above composition is prepared in a similar manner as described inExample 11.

EXAMPLE 16 A laundering composition for use in washing white fabrics isprepared with:

Parts by wt. Condensation product of tall oil and ethylene oxidecontaining 1.6 parts of ethylene oxide per part of tall oil 16.0 Sodiumtripolyphosphate 21.0 Sodium pyrophosphate 21.0 Water-soluble sodiumsolids 10.0 Carboxymethyl cellulose 1.0 Sodium salt of 2 (3"',4"dichloro stilbyl 4")- '(naphtho 1',2:4,5) 1,2,3 triazole 2" sulfonate0.03

Water 11 A similar laundering composition is obtained if, instead of thebrightener mentioned above, the same amount of the sodium salt of 2(2',4" dichloro stilbyl 4")- (naphtho 1,2':4,5) 1,2,3 triazole 2sulfonate is incorporated into the above composition.

20 EXAMPLE 17 The following liquid laundering composition is prepared,all amounts being expressed as parts by weight:

Parts Sodium alkyl benzene sulfonate (the alkyl group being derived frompolypropylene and averaging 12 A similar liquid laundering compositionis obtained if, instead of the brightener mentioned above, the sameamount of the sodium salt of 2-(2"',4"-dichloro-stilbyl- 4") (naphtho1',2':4,5) 1,2,3 triazole 2" sulfonate is incorporated into the abovecomposition.

The laundering compositions described in Examples 11- 17 inclusive arevery well suited for use in wash liquors for the laundering of cotton ornylon and afford a very good whitening eflect on these textilematerials, also in cases where the wash liquors contain active chlorinein amounts to up to 0.8 g. per liter.

EXAMPLE 18 52 g. of the sodium salt of 2-(3",4'"-dichloro-stilbyl-4")-(naphtho-1',2':4 ,5)-1,2,3-triazole 2." sulfonic acid are introducedinto 160 ml. of dry chlorobenzene, and While stirring any residual wateris removed by azeotropic distillation. Then 30 ml. of phosphorusoxychloride are added within 15 to 30 minutes at a temperature of to andthe mixture is stirred for 4 to 6 hours under reflux. After cooling, itis poured at a temperature of 0 to 5 into a total of 1500 ml. of anice-water mixture and stirred for 30 minutes; then it is filtered andthoroughly Washed with cold distilled water. The damp residue is driedin vacuo at an initial temperature of 30 to 40 *Which is then raised toto whereupon the crude product is recrystallized from boilingchlorobenzene. 2(3"',4"'-dichloro stilbyl 4")naphtho -1,2':4,5) 1,2,3-triazole-2"-sulfonic acid chloride is obtained as a yellowish powderhaving a melting point of 267 to 269 (uncorrected).

10 g. of this 2-(3"',4'-dichloro stilbyl 4")(naphtho-1,2':4,5)-1,2,3-triazole-'2"-sulfonic acid chloride are addedat a temperature of 70 to 75 to a mixture of 300 ml. of Cellosolve (96%)in 40 ml. of water and stirred for 30 to 40 hours under reflux. Whilestirring the alcohol is distilled off under normal pressure. In thecourse of the distillation, the free sulfonic acid begins to separate inthe form of a thick crystal cake. At this time, about 60 to 90 ml. ofwater are gradually added so that the reaction mixture can be furtherstirred. When a distillation temperature of 97 to 98 has been reached,the contents of the reaction vessel is cooled, filtered, washed with atotal of 200 ml. of distilled water and dried in vacuo at a temperatureof 120 to 125. 2-(3"',4'"-dichloro-stilbyl-4")-(naphtho-l',2:4,5)-1,2,3-triazole-2-sulfonic acid is obtained as a paleyellowish powder. By reacting an aqueous alcohol solution of this acidwith an equimolecular solution of potassium hydroxide, lithium hydroxideor ammonium hydroxide, the potassium or lithium or ammonium salts of the2-(3",4"'-dichlorostilbyl-4")-(naphtho-1',2:4,5)-1,2,3-triazole-2"-sulfonic acid areobtained. All of these compounds are yellowish powders. They are alsovaluable brightening agents and differ from the so- 21 dium salts onlyin their solubility and aflinity to cotton and nylon.

When in the above example the sodium salt of 2-(3",4-dichloro-stilbyl-4")-(naphtho l,2':4,5) 1,2,3 tri aZo1e-2-sulfonicacid is replaced by equal parts of the sodium salt of2-(2,4-dichloro-stil'oyl-4)-(naphthol',2:4.5)-1,2,3-triaZole-2"-sulfonicacid While methods and conditions remain otherwise unchanged, 2-(2",4-dichloro-stilbyl4")-(naphtho1,2:4.5) 1,2,3 triazole- 2-sulfonic acidchloride is obtained as a greenish-yellow powder having a melting pointof 273 to 277 (uncorrected) which further yields the free sulfonic acidand, by reaction with alkali, the corresponding alkali salts of2-(2',4-dichlorostilbyl-4)-(naphtho 1,2:4,5) 1,2, 3-triazole-2"-sulfonicacid. The free sulfonic acid as well as its alkali salts are brighteningagents which have similar properties as the above-mentioned compounds.

EXAMPLE 19 in order to obtain a storable non-soap detergenbcontainingbrightener and chlorine-yielding agent, the following components weredry blended in the proportions given below, limonene, perfume, and whitemineral oil being sprayed in the other substances of the compositionWhile tumbling them:

Parts Spray dried pentasodium tripolyphosphate 60 Sodiumdodecylbenzenesulfonate (containing approximately 3% moisture) 7.3Sodium sulfate 90 Sodium carbonate d-Limonene 0.35

Perfume 0 .35 Potassium dichlorocyanurate 30.5 White mineral oil 0.5

Sodium 2-(3"'-chloro-stilbyl-4) (naphtho 1,2:

4,5)-1,2,3-triaZole-2-sulfonate 0.35

The resulting detergent powder can be shipped and stored for at leasttwo months in bottles or paper bags and does not require any specialprecautions for protection against atmospheric moisture such ashermetically sealed, air-tight polyethylene pouches or aluminum-foilcovered cardboxes.

Detergent compositions of similar properties which are equally storableunder similar conditions are obtained by replacing in the detergentcomposition of Example 19 the optical brightener by one of thebrighteners produced according to Examples 1 and 3 or a mixture of suchbrighteners.

Similarly, potassium dichlorocyanurate can be replaced by an equalamount of the corresponding sodium salt, or by trichlorocyanuric acid,dichloroisocyanuric acid, dichloro-dimethyl-hydantoin, chlorinatedtrisodium phosphate or N,N-dichloro-benzoylene urea.

We claim:

1. An optical brightener having the formula:

where M is alkali metal, alkaline earth metal, hydrogen or ammonium.

2. An optical brightener having the formula:

where M is alkali metal, alkaline earth metal, hydrogen or ammonium.

3. An optical brightener having the formula:

Where M is alkali metal, alkaline earth metal, hydrogen or ammonium.

4. An optical brightener having the formu a:

All MOaS SOaM where M is alkali metal, alkaline earth metal, hydrogen orammonium.

5. An optical brightener having the formula:

U1 MOsS References Cited UNITED STATES PATENTS 2,784,183 3/1957 Kelleret a1 260-240 3,101,333 8/1963 Adams et a1 260240 3,119,820 1/1964 Adamset a1. 260-240 FOREIGN PATENTS 717,889 11/1954 Great Britain. 1,316,17112/1962 France.

JOHN D. RANDOLPH, Primary Examiner US. Cl. X.R.

